Low voltage transfer to battery power: Switches to battery power as line voltage decreases to 174V (220V), 182V (230V) or 190V (240V) or less. Resets back to line power mode as line voltage increases to 184V (220V), 192V (230V) or 200V (240V) volts

High voltage transfer to battery power: Switches to battery power as line voltage increases to 266V (220V), 278V (230V) or 290V (240V) or higher. Resets back to line power mode as line voltage decreases to 258V (220V), 270V (230V) or 282V (240V)